Skin Layers?

[Munderbunny]

Not that I expect anyone to answer this question, since it seems all the skinners aren't here, but....

My gf removed part of a bra layer and she could see the nipples underneathe in the game, making me wonder if there is a way to edit the actual layers in a skin? I've noticed that some things will overlap in the player skin while just trying to muck with the braids. Is there a way edit these different layers in a skin?